gov.noaa.csc.maps:2004_CT_m20eng; USAutf8datasetMike SutherlandDOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce303-497-6120303-497-6513NOAA/NESDIS/NGDC E/GC1 325 BroadwayBoulderCO80305-3328USAmike.sutherland@noaa.gov7:30am-5:00pm Mountainauthor2013-05-07ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded DataISO 19115-2:2009(E)pointNorth American Datum 1983NAD832007-01-19revisionhttp://www.epsg-registry.org/export.htm?gml=urn:ogc:def:crs:EPSG::4269NAD83Link to Geographic Markup Language (GML) description of reference system.informationresourceProviderEuropean Petroleum Survey Grouphttp://www.epsg-registry.org/European Petroleum Survey Group Geodetic Parameter RegistryRegistry that accesses the EPSG Geodetic Parameter Dataset, which is a structured dataset of Coordinate Reference Systems and Coordinate Transformations.searchpublisherurn:ogc:def:crs:EPSG::4269Ellipsoid in MetersLocal Vertical Reference2004 Connecticut Lidar2006-08-14publicationDOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce843-740-12002234 South Hobson Ave.CharlestonSC29405-2413coastal.info@noaa.govhttp://coast.noaa.govoriginatorDOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce843-740-12002234 South Hobson Ave.CharlestonSC29405-2413coastal.info@noaa.govhttp://coast.noaa.govpublisherimageDigitalLIDAR data is remotely sensed high-resolution elevation data collected by an airborne collection platform. Using a combination of laser rangefinding, GPS positioning and inertial measurement technologies; LIDAR instruments are able to make highly detailed Digital Elevation Models (DEMs) of the earth's terrain, man-made structures and vegetation. This data was collected at submeter resolution to provide nominal 1m spacing of collected points. Two returns were recorded for each pulse in addition to an intensity value. This data set is a raster file of z values with 153 columns and 61 rows. The data set was generated from a larger data set and includes all valid points within the requested geographic bounds.LIDAR data is used for 3D visualization, elevation based analysis and for feature extraction.n/acompletedDOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce843-740-12002234 South Hobson Ave.CharlestonSC29405-2413coastal.info@noaa.govhttp://coast.noaa.govpointOfContactnotPlannedBathymetry/Topographyelevationlidarlaserbeachtopographydigital elevation modelDEMerosionthemeNoneUnited StatesConnecticutNew HavenOld SaybrookQunnipiac RiverNew Haven HarborConnecticut CoastlineConnecticut RiverplaceNoneThese data depict the elevations at the time of the survey and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. Any conclusions drawn from analysis of this information are not the responsibility of NOAA or any of its partners. These data are NOT to be used for navigational purposes.While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.Lidar Final ReportCitation URLftp://ftp.csc.noaa.gov/pub/crs/beachmap/qa_docs/ct/20040415_QA_REPORT_Connecticut.pdfLidar Final ReportinformationcrossReferencevectoreng; USAelevation-72.908092-72.27993341.24004241.4538902004-10-08Reflective surface data represents the DEM created by laser energy reflected from the first surface encountered by the laser pulse. Some energy may continue beyond this initial surface to be reflected by a subsequent surface as represented by the Last Return data. Intensity information is captured from the Reflective Surface pulse and indicates the relative energy returned to the sensor as compared to the energy transmitted. The Intensity image is not calibrated or normalized but indicates differences in energy absorption due to the the interaction of the surface materials with laser energy at the wavelength transmitted by the sensor. Points are classified as on ground surface or not on ground surface to support creation of a bare earth model from the data. Open water is classified as not bare ground.LAZDOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce843-740-12002234 South Hobson Ave.CharlestonSC29405-2413coastal.info@noaa.govhttp://coast.noaa.govdistributorThe National Geophysical Data Center serves as the archive for this LIDAR data. NGDC should only be contacted for this data if it cannot be obtained from
NOAA Coastal Services Center.Mike SutherlandDOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce303-497-6120303-497-6513NOAA/NESDIS/NGDC E/GC1 325 BroadwayBoulderCO80305-3328USAmike.sutherland@noaa.gov7:30am-5:00pm MountaindistributorThe National Geophysical Data Center serves as the archive for this LIDAR dataset. NGDC should only be contacted for the data if it cannot be obtained from
NOAA Coastal Services Center.datasetHorizontal Positional Accuracy ReportHorizontal accuracy can be characterized by the rule of thumb of 1/2000th of flying height or roughly 0.5 meters for this collect. Spot checks in the field routinely are measured at 1/4000th of flying height but are not formally characterized.Horizontal Positional AccuracyAccuracy units - metersmeters0.5Vertical Positional Accuracy ReportThe vertical accuracy was tested following the National Standards for Spatial Data Accuracy. Based on a total of 22 points the average error between the bare earth LiDAR coverage and the control was 0.002 m with a root mean square error (RMSE) of 0.057 m.Vertical Positional AccuracyAverage error between Bare Earth LiDAR coverage and control. Accuracy units - metersmeters0.002Vertical Positional AccuracyRoot Mean Square Error (RMSE) Accuracy units - metersmeters0.057LIDAR raster data is visually inspected for completeness to ensure that any gaps between flight lines or loss of signal represents less than 5% of required collection area. Areas of open water where loss of LIDAR signal is common are corrected to the best estimate of water level at time of collection. LIDAR is self-illuminating and has minimal cloud penetration capability. Water vapor in steam plumes or particulates in smoke may cause reflection of LIDAR signals and loss of elevation information beneath these plumes. Glass structures and roofs may appear transparent to the LIDAR signal and therefore may not register on the reflective surface. Some asphalt formulations have been shown to absorb topographic LIDAR wavelength energy resulting in "pitting" of roof surfaces using this material.All LAS formatted LIDAR data are validated using commercial GIS software to ensure proper formatting and loading before delivery. This validation procedure ensures that data on delivery media is in correct physical format and is readable.Data Collection: Using a LH Systems ALS50 Light Detection And Ranging (LiDAR) system, 41 flight lines of high density (submeter ground sample distance) data were collected over areas in coastal Connecticut (approximately 300 square kilometers). Two returns were recorded for each laser pulse along with an intensity value for each return. The data acquisition occurred in one (1) mission on October 8, 2004. Three (3) airborne global positioning system (GPS) base stations were used to support the LiDAR data acquisition: Moriches 1 continuously operating reference station (CORS) ARP, NGS point P36, and one station Woolpert located using static GPS positioning methods, Madison CP. In addition, twenty-two control points were surveyed through fast-static GPS methods to support the final accuracy analysis and tied into the National Geodetic Survey (NGS) points Moriches CORS and P36.2004-10-01T00:00:00Airborne GPS Processing: Airborne GPS data was differentially processed and integrated with the post processed IMU data to derive a smoothed best estimate of trajectory (SBET). The SBET was used to reduce the LiDAR slant range measurements to a raw reflective surface for each flight line. The overlap between flight lines was removed to provide a homogeneous coverage, and the coverage was classified to extract a bare earth digital elevation model (DEM). Airborne GPS is differentially processed using the GrafNAV V4.10 software by Waypoint Consulting of Calgary, Alberta, Canada. The PDOP and distance separation is as follows: P36: Maximum PDOP = 3.58 (maximum) Average Distance Separation: 17 km Madison CP: Maximum PDOP = 3.58 (maximum) Average Distance Separation: 19 km IMU data is processed using the PosPac V4.2 software by Applanix Corporation of Richmond Hill, Ontario, Canada. The reflective surface is derived using the ALS Post Processor software by Leica Geosystems GIS & Mapping Division of Atlanta, Georgia. The classification and quality control (QC) of LiDAR data is carried out using a combination of proprietary software and TerraScan software by Terrasolid Limited of Helinski, Finland. Two (2) coverages were delivered in the LAS file format: bare-earth and above ground features.2004-11-01T00:00:00IMU data Processing: IMU data provides information concerning roll, pitch and yaw of collection platform during collection event. IMU information allows the pulse vector to be properly placed in 3D space allowing the distance from the aircraft reference point to be properly positioned on the elevation model surface. IMU data is processed using the PosPac V4.2 software by Applanix Corporation of Richmond Hill, Ontario, Canada.2004-11-01T00:00:00Reflective Surface Generation: The reflective surface is derived using the ALS Post Processor software by Leica Geosystems GIS & Mapping Division of Atlanta, Georgia.2004-11-01T00:00:00LIDAR Point Classification The classification and quality control (QC) of LiDAR data is carried out using a combination of proprietary software and TerraScan software by Terrasolid Limited of Helinski, Finland.2004-12-01T00:00:00Output LAS Files Random LIDAR points maintained in UTM coordinate system converted to Geographic projection with units of Decimal Degrees2005-01-01T00:00:00The NOAA Coastal Services Center (CSC) received files in LAS format. The files contained LiDAR intensity and elevation measurements. CSC performed the following processing on the data to make it available within the LiDAR Data Retrieval Tool (LDART): 1. The las files were converted from State Plane coordinates to Geographic coordinates. 2. The las header fields were sorted by latitude and updated. 3. The data were converted from orthometric to ellipsoidal heights using Geoid03.2006-09-27T00:00:00DOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce843-740-12002234 South Hobson Ave.CharlestonSC29405-2413coastal.info@noaa.govhttp://coast.noaa.govprocessorThe NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp transfer from the NOAA Coastal Services Center. The data are
currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are archived in LAS
or LAZ format. The LAS format is an industry standard for LiDAR data developed by the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless
compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data
are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most up to date geoid model when transforming to orthometric
heights.2006-01-03T00:00:00Pamela GrotheDOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of CommerceContact Data CenterprocessorSource Contribution: System Calibration. Minimizes horizontal error caused by IMU mis-alignment by checking over known range and by comparing positional results from adjacent flight lines to compute error adjustment function. Source Type: Validation ReportCollection System CalibrationpublicationWoolpert LLPoriginatorThe ALS50 calibration and system performance is verified on a periodic basis using Woolpert's calibration range. The calibration range consists of a large building and runway. The edges of the building and control points along the runway have been located using conventional survey methods. Inertial measurement unit (IMU) misalignment angles and horizontal accuracy are calculated by comparing the position of the building edges between opposing flight lines. The scanner scale factor and vertical accuracy is calculated through comparison of LiDAR data against control points along the runway. Field calibration is performed on all flight lines to refine the IMU misalignment angles. IMU misalignment angles are calculated from the relative displacement of features within the overlap region of adjacent (and opposing) flight lines. The raw LiDAR data is reduced using the refined misalignment angles.annually2014-05-07This metadata was automatically generated from the FGDC Content Standards for Digital Geospatial Metadata standard (version FGDC-STD-001-1998) using the 2013-01-04 version of the FGDC RSE to ISO 19115-2 for LiDAR transform.Translated from FGDC 2013-05-07T15:16:54.518-06:00Last Metadata Review Date: 2011-11-19